This invention relates to rendering a silhouette edge of a three-dimensional (xe2x80x9c3Dxe2x80x9d) model.
Silhouette edges are outlines of a 3D model and its interior features. Silhouette edges are detected based on the intersection of front and back facing polygons that make up the 3D model. Computer programs are used to detect, and render, silhouette edges to form a two-dimensional (xe2x80x9c2Dxe2x80x9d) image from the 3D model. How those edges are rendered affects the look of the 2D image.
In general, in one aspect of the invention, silhouettes edges of a 3D model are detected and rendered in a format that corresponds to the geometry of the 3D model.
Among the advantages of the invention are one or more of the following. Rendering the silhouette edges in a format that corresponds to the geometry of the 3D model produces a 2D image that more closely approximates the 3D model. For example, curvature in the original 3D model can be detected, and curved silhouette edges can be selected to preserve the curvature of the original 3D model.
Other advantages and features will become apparent from the following description and the claims.